1) Field of the Invention
The present invention relates to the field of graphene biosensors.
2) Description of Related Art
Graphene [Novoselov, K. S. et al. Science 306.5696 (2004)], one of the exotic new nanomaterials of the 21st century, is a two-dimensional sheet comprised solely of sp2 carbon atoms arranged in a chicken-wire like framework [Geim, A. K. & P. Kim. Scientific American 298.4 (2008); Geim, A. K. Science 324.5934 (2009); V. I. Falko, A. K. Geim, Eur. Phy. J—Special Topics 148 (2007); Schedin, F. et al. Nature materials 6.9 (2007)]. Graphene possesses outstanding electronic [Neto, A. H. C. et al. Reviews of modern physics 81.1 (2009); Peres, N. M. R., F. Guinea, & A. H. C. Neto. Physical Review B 73.12 (2006); Novoselov, K. S. et al. Physica status solidi (B) 244.11 (2007)], mechanical [Booth, T. J. et al. Nano letters 8.8 (2008); Meyer, J. C. et al. Solid State Communications 143.1 (2007); Scharfenberg, Scott, et al. Applied Physics Letters 98.9 (2011)], thermal [Clement, F. et al. CS Nano 4 (2010); Balandin, Alexander A. Nature materials 10.8 (2011); Balandin, A. A. et al. Nano letters 8.3 (2008)], optical [Kim, K. S. et al. Nature 457.7230 (2009); Bae, S. et al. Nature nanotechnology 5.8 (2010)] and charge transport [Cho, S. & M. S. Fuhrer. Physical Review B 77.8 (2008); Han, M. Y. et al. Physical review letters 104.5 (2010)] properties that make it an attractive choice for biosensors [Alwarappan, S. et al. Journal of Physical Chemistry C 113.20 (2009); Alwarappan, S. et al. Journal of Physical Chemistry C 114.30 (2010); Tang, Z. et al. Small 6.11 (2010); L. Zhu et al. Biosens. and Bioelectron. 35 (2012); F. Li et al. Nanoscale 2.6 (2010)], fuel cells [Liu, C. et al. Biosensors and Bioelectronics 25.7 (2010); Seger, B. & P. Kamat. Journal of Physical Chemistry C 113.19 (2009)], batteries [Wu, Z.-S. et al. ACS nano 4.6 (2010); Min, P. S. et al. Nano letters, 9 (2009)], ultracapacitors [Stoller, M. D. et al. Nano letters 8.10 (2008); Liu, C. et al. Nano letters 10.12 (2010)], electromechanical resonators [Bunch, J. S. et al. Science 315.5811 (2007); Chen, C. et al. Nature nanotechnology 4.12 (2009)] and field effect transistors [Lin, Y.-M. et al. Nano Letters 9.1 (2008); Schwierz, F. Nature nanotechnology 5.7 (2010)].
Altered DNA sequences in specific genes are characteristic of many diseases from cancer to asthma and their identification is important for correct diagnosis and treatment. While DNA mutations or single-nucleotide polymorphisms can be detected by direct sequencing or PCR, these methods require costly instruments, extensive training and relatively long run times. A rapid, inexpensive, specific, and sensitive device for detecting mismatched DNAs that could be used in the field or during a clinic visit would prove invaluable to physicians, especially in resource-limited areas.